Locking device



Aug. 26, 1952 CASTLE 2,608,085

LOCKING DEVICE Filed July 25, 1947 1/IIIII/I/II/IIIIIII/lIIII/I/IIII/IIl/I/IlI/I/fl 7/III/IIIII/II/IIIIII/I/IIII/I M w 20 V H K k 7 E 3 29 g M IN VEN TOR. W 1% @942? Patented Aug. 26, 1952 I I roonmonnvron l Alfr d B Gris Brookmont,

--Generally, the present invention relates to locking devicesandmore particularly to locking devices for use with closures of the type protecting manholes, subterranean vaults, andthe like. It is to be distinctly understood, however, that. my inventive concept is. not thuslimited, since it may be employed with efficacy in numerous other closure arrangements.

Certain problems are present in providing a suitable locking mechanism for relatively heavy closures such as are used .for sealing manhole apertures and vaults having gratings or. solid cov-. ers. For instance, conventional locks require, the useof a key to manipulate, the locking mechanism and then to raise or lower the cover aseparate t l o handle on the closure is. required. In ad tion,--such closures are generally-located in the street or pavement, with the attendant result that dirt or other foreign matter often enters the working parts of the lock and impairs its proper operation.

A primary object of my invention .is toprovide a locking device of the character described which overcomes the above and other objectionable features inherent in the prior art devices.

A further object of my invention is to provide a locking mechanism for closures wherein the k also f ns asthe and e to o en t closure. V I 7 Yet another object of the present invention is to provide a lockingmechanism which includes few essential working parts, which is positive in action and which can be inexpensively manufactured.

Still another object of my invention is to provide a locking mechanism for relatively heavy closure members wherein the operating mechanism is so designed that tampering therewith by unauthorized persons is quite diflicult.

With the foregoing and other objects in view, the invention consists in the details of construction, and in the arrangement and combination of parts to be hereinafter more fully set forth and claimed.

In describing the invention in detail, reference will be had to the accompanying drawings forming part of this application wherein like characters denote corresponding parts in the several views, and in which:

Figure l is a side elevational view of the key employed to actuate the locking mechanism;

Figure 2 is a longitudinal sectional view of the locking mechanism;

Figure 3 is a plan view of my locking device.

As best shown in Figure 2, the locking device includes a metal housing l having top, end, and

i F. App icat on July as, 1947, Serial No. 762,958

" faclaims. (01. -169) side walls, i I, I2 and I3, respectively. While I prefer that the housing It] is cast as a unitary unit, it is, of course, to be understood that it may be fabricated in other'ways. A bolt, designated generally It, is mounted within the, housing In for longitudinal sliding movement. The

bolt includes a latch member l5 adapted tocooperate with a keeper (not shown), an enlarged intermediate portion l6, and a reduced exten sion l7. As was the case of the housing It], the elements l5, l6 and I1 are also preferably formed as an integral unit.

It can be seen from Figure 2 that the end walls 12 are formed with alined apertures 18 which serve as bearings for the latch l5 and the reduced extension l1. 'Thediameterof the apertures I 8 is such that ample clearance is provided for the sliding movement of the bolt I4 and yet prevent the entry of dirt, grit, or the like, into the interior of the housing lll. A helical spring I 9 surrounds the extension I! and one end thereof bears against wall 12 while the other contacts the intermediate portion i6 whereby" the bolt is normally maintained in the closed or locked position.

To guard against tampering-with the locking mechanism, it will be observed that the top wall I] is provided with. a shelf 20 which extends a substantial distance beyond the end of the extension I! when the bolt is in its locked position. Also, to improvev the. external appearan e of th devi .I provide. accyer plate 21' wh ch is S r t i t p wall I! by any suit able means such as spot welding, bolts, or the like. In certain circumstances, it may be advisable to dispense with the cover plate.

The intermediate portion l6 of the bolt is formed with a recessed area 22 having a cam or contact surface 24 and a substantially vertical wall 25. An elongated key slot 26 in the top wall II and a similar slot 21 in the cover plate communicate with the recessed area 22, for a purpose to be hereinafter more fully described.

To operate the locking mechanism, there is provided a key 23 having a body portion 29 and a cam surface 30 at one end thereof. The other end of the body 29 carries a handle or grip member 3| for proper manipulation of the key.

When it is desired to unlock the bolt mechanism, the cam portion 38 of the key is inserted through the slots 26 and 21 into the recessed area 22, and upon movement of the key toward the right (Fig. 2) the cam 30 will cam the surface 24 toward the left, thus compressing the spring l9 and effect withdrawal of the latch l5 from its keeper. After the bolt is unlocked, the

closure may be raised by the handle, thus enabling the key 28 to serve not only as a means for unlatching the bolt, but also as a means for raising the closure. When it is desired to lock the closure, the key 28 is withdrawn from the recess 22 and the closure is dropped or shoved into place, whereupon the spring I9 will urge the bolt l4 into its locked position.

By virtue of the recess 22 having the cam surface 24 in combination with the relatively small size of the slots 26 and 21, the danger of unauthorized personnel successfully unlocking the device is reduced to a minimum. For example,iif

a straight edge tool was inserted into the recess so as to bear against the cam surface,

it would merely slide down such surface and not cam the bolt rearwardly against the action of the spring I9.

Another distinct advantage of my improve ment is that the recess 22 is not likely to retain dirt or the like. which may find access through the slots 26 and 21 and thus impair or otherwise adversely affect the proper functioning of the moving parts. If, however, for some reason the spring l9, "fails to return the bolt It to its locked position, this defect may be readily rectified by inserting the key 28 into the recess 22 with the cam 30 thereof in contact with the wall 25. and, upon applyingpressure to the key, the latch will be forced into proper relationship with its keeper. v

It will be appreciated from the above that there is provided a locking mechanism for closures which is rugged in design and which can be quickly and easily operated. Inaddition, the relationship between the key slotsand the actuating mechanism of the bolt is such that unauthorized tampering is very diflicult. Furthermore, due to therelatively simple nature of the mechanism, it is well adapted for use with all types of closures, regardless of the plane in which such closures operate.

I claim:

1. A locking mechanism for closures, comprising a support, a bolt having a latching portion mounted for, longitudinal sliding movement with respect to said support, a spring means cooperating with the bolt and the support normally maintaining the latching portion in a locked position, the said bolt being'provided with an elongated slot extending therethrough and axially of the bolt, the support having an entrance opening of lesser length than the elongated slot registering with the slot, the end Wall of the elongated slot remote from the latching portion being inclined in a direction away from the latching portion,

the wall of the entrance opening in proximity to the inclined wall of the elongated slot bein spaced from said inclined wall in the direction of the latching portion whereby it is necessary that a tool having a curved end portion be employed, the curved end portion being inserted through the entrance opening into the slot and moved in a direction toward the inclined wall, the curved end portion of the tool engaging the inclined wall and thus moving the ,bolt; against the action of the spring means to unlock the bolt.

2. A locking mechanism for closures, comprising a support, a bolt mounted for longitudinal sliding movement with respect to said support, the said bolt having a latch portion, a reduced extension, and an enlarged portion intermediate the latch portion and the extension, spring means surrounding the extension and bearing against said support to maintain normally the latch portion in a locked position,the said enlarged portion being provided with an elongated slot extending therethrough and axially of the enlarged portion, the support having an entrance opening of lesser length than the elongated slot registering with said elongated slot, the end wall of the slot remote from the latch portion being inclined in a direction away from the latch portion, the wall of the entrance opening in proximity to the inclined wall of the slot being spaced from the said inclined wall in the direction of the latch portion. whereby it is necessary that a tool having a curved end portion be employed, the curved end portion being inserted through the entrance opening into the elongated slot and moved in a direction towards the inclined wall, the curved end portion of the tool engaging the inclined wall and moving the bolt against the-action of the spring means to unlock the bolt.

ALFRED B. CASTLE.

REFERENCE S CITED UNITED STATES PATENTS Number Name Date 317,153 Lowrie May 5, 1885 641,471 Scheel Jan. 16, 1900 1,265,767 Fout's May 14, 1918 1,884,722 1 Katz Oct. 25, 1932 2,336,458 Bales et al Dec. 14, 1943 FOREIGN PATENTS Number Country Date France Feb. 6, 1939 

